Presentation Details
| UV-Induced Degradation in TOPCon Modules: Linking Accelerated Testing and Field Evidence Archana Sinha1, Jean-Nicolas Jaubert1, Todd Karin1, Dana Kern2. 1Kiwa PVEL, Napa, CA, USA.2National Laboratory of the Rockies, Golden, CO, USA |
Abstract
Modern Tunnel Oxide Passivated Contact (TOPCon) modules have exhibited greater power degradation in specific bills of materials (BOMs) under accelerated ultraviolet light-induced degradation (UVID) testing. The testing revealed a broad range of power degradation (0.6% to 16%) after UV dose of 120 kWh/m2 (280-400 nm) using metal halide lamps or equivalent dose of 50 kWh/m2 (280-400 nm) using UV fluorescent lamps. The power loss due to UVID is primarily driven by a reduction in Voc, consistent with passivation loss or a decrease in effective carrier lifetime. A subset of BOMs also showed higher Isc losses, whereas the contribution from FF degradation remained minimal. Notably, the characteristic UVID signatures observed in EL images during lab testing were also identified in field-deployed modules, supporting a strong correlation between accelerated UVID test results and real-world module performance. After one-year of outdoor exposure in Davis, California, the power degradation of fielded modules primarily ranged from 0.4% to 6%. A small number of modules exhibited power losses exceeding 10%, which are attributed to dark metastability effects. Higher power degradation observed under accelerated UVID testing compared to the field exposure is attributed to short-circuit operating condition during chamber testing and mitigating effects of light soaking experienced by modules in the field.
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No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author.